Which is something that Horde players online also do and even blame him for Sylvanas getting killed by Arthas and then nuking Teldrassil. I once saw a Horde player who unironically, genuinely, with a straight face blamed Terenas for the Burning of Teldrassil and said that Terenas was responsible for the Burning of Teldrassil. So your attempt at a "gotcha!" moment failed.
Aside from that, no, they are not the same situation at all. Considering how Zul was Rastakhan's direct subordinate and council advisor, while the leaders of the Scourge were not, actually, Terenas' subordinates. Ner'zhul was an orc, Mal'ganis was a Nathrezim, and Kel'thuzad was a citizen of Dalaran.
There's also the fact that, unlike Rastakhan, Terenas was growing quite senile and weak, this is Canonically acknowledged in-universe by Salramm the Fleshcrafter, a necromancer who took part in the Culling of Stratholme:
So, unlike Rastakhan, and in his defence, Terenas had grown quite senile by the time of the Scourge (due to having ruled for so long for a human), so understandably he wasn't quick to react against the Scourge. He also had an entire orcish uprising to deal with in the south as all the internment camps were being taken over by the rebels.[Talking to Arthas] Go sniff somewhere else pup. You'd best crawl back to your senile father and await the end of your reign
And there's also the fact, you know, that even after hearing that Zul declared war on the rest of the world, Rastakhan still kept him around as his chief advisor in his royal council.
The irony, when Sylvanas had committed genocide 10 minutes earlier.Also worth noting that the Alliance and Horde fought off the Zandalar together in both expansions. You can't call yourself peaceful and just when fucking Sylvanas takes a more diplomatic approach than you do.
And following your logic, you can make the same argument with the Dark Irons. Both factions fought them in the past, but only the Alliance confronted them with a more diplomatic approach.
After said leader already threw them under the bus, in the case of Garrosh (when he tried to have the PC and Vol'jin assassinated in that cave) and potentially never in the case of the Loyalist PC, when it comes to Sylvanas.he PCs consult with sane leaders and individuals of the faction, observe just how far the warchief is willing to go, and take part in an uprising to be rid of him/her when it becomes certain they can't be redeemed
What exactly is this referring to? The Alliance suicide mission to Nazmir? Yes, Rastakhan was foolish to fall for that, which once again makes me wonder why anyone would mourn him. He literally didn't accomplish anything of note for Zandalar in the short time we had with him in-game.'look Nazmir's a bit misty, let's throw the entirety of our armed forces at it and leave our home base completely unprotected!'.